Ozgun Eray, Sayilan Ozgun Gulben, Tabakcioglu Kiymet, Suer Gokmen Selma, Sut Necdet, Eskiocak Sevgi
Department of Medical Biochemistry, Trakya University School of Medicine, 22030 Edirne,
Gen Physiol Biophys. 2017 Oct;36(4):465-470. doi: 10.4149/gpb_2017005. Epub 2017 Jun 27.
Paraoxonase-1 (PON1) and PON3 (PON3) are anti-atherosclerotic enzymes, synthesized primarily in liver and bound to HDL in circulation. The aim of the present study was to investigate the effects of therapeutic doses of lipoic acid on PON1 and PON3 protein levels, mRNA expression and arylesterase activity in liver. We treated HepG2 cells with 10, 40 and 200 μM lipoic acid for 72 h. Cell viability was evaluated by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide assay. PON1 and PON3 protein levels were measured by Western blotting, their mRNA expression was measured by quantitative PCR and arylesterase activity was measured spectrophotometrically. 200 µM lipoic acid caused a significant increase on PON1 and PON3 protein levels and arylesterase activity as compared with control, 10 µM and 40 µM lipoic acid-treated cells. 200 µM lipoic acid also caused a significant decrease on PON1 mRNA expression whereas on a significant increase PON3 mRNA expression as compared with control, 10 µM and 40 µM lipoic acid-treated cells. Our study showed that although lipoic acid up-regulates PON3 but down-regulates PON1 mRNA expression, it increases both PON1 and PON3 protein levels and arylesterase activity in HepG2 cells. We can report that lipoic acid may be useful for preventing atherosclerosis at therapeutic doses.
对氧磷酶-1（PON1）和对氧磷酶-3（PON3）是抗动脉粥样硬化酶，主要在肝脏中合成，并在循环中与高密度脂蛋白（HDL）结合。本研究的目的是探讨治疗剂量的硫辛酸对肝脏中PON1和PON3蛋白水平、mRNA表达及芳基酯酶活性的影响。我们用10、40和200μM硫辛酸处理HepG2细胞72小时。通过3-（4,5-二甲基-2-噻唑基）-2,5-二苯基-2H-四唑溴盐法评估细胞活力。通过蛋白质印迹法测量PON1和PON3蛋白水平，通过定量PCR测量它们的mRNA表达，并通过分光光度法测量芳基酯酶活性。与对照、10μM和40μM硫辛酸处理的细胞相比，200μM硫辛酸导致PON1和PON3蛋白水平及芳基酯酶活性显著增加。与对照、10μM和40μM硫辛酸处理的细胞相比，200μM硫辛酸还导致PON1 mRNA表达显著降低，而PON3 mRNA表达显著增加。我们的研究表明，虽然硫辛酸上调PON3但下调PON1 mRNA表达，但它增加了HepG2细胞中PON1和PON3蛋白水平及芳基酯酶活性。我们可以报告，硫辛酸在治疗剂量下可能有助于预防动脉粥样硬化。
